European Space Agency shelves Ariane 6 Block 3 upgrades amid cost concerns

Since its debut two years ago, Ariane 6 has completed eight orbital flights without incident, delivering over 20 metric tons to low-Earth orbit. Despite this track record, the European Space Agency announced on Thursday that the Block 3 suite of upgrades, notably the carbon-composite ICARUS upper stage, will be put on hold. The cancellation may delay ESA’s planned scientific missions, including a probe targeting Enceladus, Saturn’s icy moon.

The move reflects growing pressure from European ministers over the vehicle’s launch cost, which Arianespace has not disclosed but is believed to lie in the €80 million-€100 million range. Ariane 6 remains a key asset for European satellite operators and for Amazon, which has contracted 18 launches for its Leo constellation, three of which have already taken place this year. The decision raises questions about the long-term viability of the program as Europe seeks to maintain independent access to space after ending reliance on Russian rockets.